Add mypy static type checker #232

	name: pytest

	on:
	pull_request:
	push:
	branches: [main]

	jobs:
	pytest:
	runs-on: ubuntu-latest
	steps:
	#----------------------------------------------
	# check-out repo and set-up python
	#----------------------------------------------
	- name: Check out repository
	uses: actions/checkout@v4
	- name: Set up python
	id: setup-python
	uses: actions/setup-python@v5
	with:
	python-version: "3.9"
	#----------------------------------------------
	# ----- install & configure poetry -----
	#----------------------------------------------
	- name: Install Poetry
	uses: snok/install-poetry@v1
	with:
	virtualenvs-create: true
	virtualenvs-in-project: true
	installer-parallel: true

	#----------------------------------------------
	# load cached venv if cache exists
	#----------------------------------------------
	- name: Load cached venv
	id: cached-poetry-dependencies
	uses: actions/cache@v3
	with:
	path: .venv
	key: venv-${{ runner.os }}-${{ steps.setup-python.outputs.python-version }}-${{ hashFiles('**/poetry.lock') }}
	#----------------------------------------------
	# install dependencies if cache does not exist
	#----------------------------------------------
	- name: Install dependencies
	if: steps.cached-poetry-dependencies.outputs.cache-hit != 'true'
	run: poetry install --no-interaction --all-extras --with dev
	#----------------------------------------------
	# run test suite
	#----------------------------------------------
	- name: Run tests
	run: poetry run pytest tests/

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